EMD SD70ACe - Norfolk Southern #1070
Photo by Jacob Boslet

Years built

2005 – 2015


Electro-Motive Diesel (EMD)

Number Produced




Years in Operation

See article

Fleet Numbers



C-C (Co'-Co')
B-B-B-B (Bo'-Bo'-Bo'-Bo') for SD70ACe-BB

Type of Diesel Train

Diesel locomotive

Number Operational


Number Preserved


Number Scrapped


(l × w × h)


Prime mover(s)

EMD 16-710-G3 2-stroke diesel


1,435 mm (4 ft 8½ in)

Maximum speed


V - E - T - D

The EMD/Progress Rail SD70ACe is a six-axle, 4300- horsepower, AC-traction diesel locomotive which was first introduced in 2004, and was produced from 2005-2015. The SD70ACe is no longer in production in the United States due to its EMD 710 engine's failure to meet EPA Tier 4 emissions regulations.


The EMD SD70ACe was born out of necessity, with EPA Tier 2 regulations off in the distance EMD had to design a new locomotive to meet these standards. The SD70ACe and its variants have sold thousands of domestic and foreign units since 2004.

CSX purchased 20 pre-production SD70ACe's. These units were retired in 2017 and sold to Progress Rail. Union Pacific was the model's second customer, and now rosters 680+ units. BNSF rosters 650 SD70ACe's (20 of which are SD70ACe-P4's). Norfolk Southern, KCS, Montana Rail Link, and Arkansas & Missouri also roster SD70ACe's. EMD had a 30 unit SD70ACe order from CN, but the order has been cancelled. CN has since purchased four EMD SD70ACe-P6 units, still adorned in patched EMDX demonstrator paint. Tacoma Rail began operating two SD70ACe-P4's leased from EMD in 2014.

On January 1, 2015, the EPA's Tier 4 emissions regulations went into effect, making it illegal for EMD to continue production of the SD70ACe as it was. Although EMD had initially thought their 710 prime mover would be able to meet Tier 4 standards, it failed to do so. EMD pressed on the the development of the SD70ACe-T4: a tier-4 compliant SD70ACe.

Despite the new Tier 4 regulations, railroads can bank their credits built up with EMD to acquire Tier 4 credit (T4C) locomotives. Union Pacific has done this, ordering additional SD70AH's in the 8997 - 9096 number range. Additionally, Norfolk Southern went back to EMD in 2018 for 40 T4C ACe's, which will be numbered 1175 - 1214).

EMD displayed its SD70ACe-T4 demo unit at the Railway Interchange show in Minneapolis. This unit is related to the SD70ACe only by a name. The unit features the new EMD 12-cylinder 1010 prime mover (vs the 16-710), producing 4,400 hp, in addition to a restyled (non-iso) cab and new HTCR-6 lighter-weight trucks. EMD plans to have 5 demos testing on the Union Pacific by the end of this year. Full production is set to begin 2nd Quarter, 2016. Union Pacific is the launch customer for the SD70ACe-T4; it placed an order for 65 units due at the end of 2016, the first of which, no. 3013, was delivered in early November of 2016.


  • Arkansas and Missouri (QTY:3) #'s 70-72. Ex-EMDX 1201-1203.

    SD70ACe-T4. Photo by Jim Wrinn

  • BNSF: (QTY:650) #'s 8400-8499, 8500-8519 (SD70ACe-P4's), 8520-8599, 8749-8799, 9000-9158, and 9160-9399.
  • CN: (QTY:4) #'s 8100-8103 (Ex-EMDX SD70ACe-P6 Demos #1206,1208,1209,1210).
  • CSX: (QTY:20) #'s 4831-4850. All retired.
  • FXE: (QTY:116) #'s 4000-4115
  • KCS: (QTY:178) #'s 3997-4199. 3997-3999 are ex EMDX Demos; 4060-4099 are KCSM. 
  • MRL (QTY:23) #'s 4300-4315, 4400-4403. 4400-4401 built July 2013; 4402-4403 built December 2013. 4404-4408 arrived in Spring 2014
  • NS (QTY:215) #'s 1000-1214. 1065-1074 are adorned in NS Heritage paint schemes. (1125-1174 have piping in place to allow for the eventual installation of equipment in order to burn LNG.) 10 on order for late 2019 delivery. 
  • QNS&L (QTY:23) #'s 501-523.
  • Tacoma Rail (QTY:2) #'s 7000-7001 (ex-EMDX #1211-1212 SD70ACe-P4's)
  • UP (QTY:687) #'s 1982, 1983, 1988, 1989, 1995, 1996, 4141, 8309-8378, 8380-8382, 8384-8395, 8397-8422, 8424-8996, 8997-9062. Models after 8823 are designated SD70AH (heavier version SD70ACe). Models after 8997 are Tier 4 Credit SD70ACe's.


  • SD70ACe: Regular SD70ACe. (One traction inverter per truck.)
  • SD70ACe-P4: SD70ACe with four powered axles. B1-1B truck arrangement. The two axles nearest to the fuel tank are unpowered. Introduced in 2012 in direct response to GE's ES44C4 model.
  • SD70ACe-P6: SD70ACe with individual axle inverter control; each individual axle powered per truck
  • SD70ACe/45: Broad-gauge, produced by EMD plant in Brazil. It has three radiator fans on top roof since it uses the same carbody of the SD80ACe developed to EMD Canada to Vale mining in Brazil.
  • SD70ACe-T4: EMD's new line haul road locomotive meeting Tier 4 standards. The unit is designated as an SD70ACe for marketing reasons.
  • SD70ACE-BB: A narrow gauge version of the SD70ACE.


Although it is a successful type of locomotive, the EMD SD70ACe has experienced several defects, mainly with the cab. Despite having a unique design, the actual design often made it difficult to maintain the writing and access to the microprocessor components at the beginning for railroad employees. BNSF has relegated its 70 SD70ACe's that are not IsoCab to the state of final unit only. After the collision in Red Oaks, Iowa, which caused the death of the train crew aboard an SD70ACe, BNSF detected that the cabin can be separated and flattened in collisions. To date, there have been no redesign changes.


The main way of distinguishing an SD70ACe from an SD70M-2 is by box on the left side of each unit, with a SD70ACe having louvered vents - on the SD70M-2, these are plated over. There is no significant difference in external appearance between an SD70ACe and an SD70ACe-P4, except for the missing traction motor on the axle closest to the fuel tank on the P4 model.

IMG 9527 edited

A photo to show one of the main spotting features between an SD70ACe and SD70M-2. Original photo credit: Terry Cantrell.


  • Union Pacific and BNSF Railway have the largest fleets of SD70ACe's - UP has 687, while BNSF has 650.
  • The SD70ACe was the last type of production diesel locomotive produced by EMD under GM's ownership, and the first under CAT/Progress Rail. 
  • The EMD SD70ACe (as well as the actual SD70 Series) was also the last type of diesel locomotive to be built in EMD's LaGrange, Illinois plant, as well as the last to be built in their London, Ontario shops, and the first to be built in EMD's new Muncie, Indiana facility.
  • In 2012, EMD introduced the SD70ACe-P4 in direct response to GE's ES44C4. The P4 is a B1-1B model (axles closest to the fuel tank are unpowered).
  • As of 2014, BNSF and Tacoma Rail are the only railroads to own SD70ACe-P4's, and CN is the only owner of SD70ACe-P6's.
  • Both UP and NS have specially-painted "heritage units" or SD70ACe units which are painted in commemorative schemes which are meant to designate former railroads which they purchased or operate over former trackage. (Such as the NS having trackage over former NYC rails, as well as the UP's purchase of the SP.)
  • The locomotive's design was mainly inspired from that of the SD80MAC and SD90MAC. This is evident in the model's large rear radiator "fins" or "wings", the rear-located dynamic brakes, and the tight, angular housing of the prime mover. Several new features were inspired by GE's newest AC locomotives, including a large radiator cabinet placed on one side, and airtanks placed on another. The cab is an updated version of EMD's Phase II cab used on the SD90MAC-H.
  • Several foreign versions also exist as well.
  • To celebrate the opening of CAT/EMD's Muncie, Indiana facility, EMD painted EMDX #1201; an SD70ACe, in a unique CAT scheme of yellow, black, silver, and chrome.
  • The SD70ACe was also the first type of locomotive to use the once-exclusive Nathan K5LLA horn, which is a 1L chime variant of the original K5LA.
  • Earlier KCS (Kansas City Southern) SD70ACe units owned by the railroad were painted in the railroad's generic grey with yellow stripes scheme, and were some of the last locomotives on the railroad's roster to be painted in such scheme before the classic or vintage-esque "Belle" scheme was eventually developed.
  • Union Pacific 4141, the George Bush 41, will be put on display at the George H. W. Bush Presidential Library.



Community content is available under CC-BY-SA unless otherwise noted.